Patch RecordWriteStub after adding it to the stub cache not during generation.

src/code-stubs.cc

 // Copyright 2011 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 102 matching lines @@
     RecordCodeGeneration(*new_object, &masm);
     FinishCode(*new_object);
 
     // Update the dictionary and the root in Heap.
     Handle<NumberDictionary> dict =
         factory->DictionaryAtNumberPut(
             Handle<NumberDictionary>(heap->code_stubs()),
             GetKey(),
             new_object);
     heap->public_set_code_stubs(*dict);
-
     code = *new_object;
+    if (MajorKey() == RecordWrite) {
+      heap->incremental_marking()->ActivateGeneratedStub(code);

[Lasse Reichstein, 2011/07/12 06:44:16]

Seems like the wrong direction of dependency, to make the CodeStub superclass
know about a specific kind of subclass.
How about calling a virtual callback function on the stub that only do something
if it's needed.

[Vyacheslav Egorov (Chromium), 2011/07/12 11:17:11]

I did not want to introduce two virtual function for such a small thingy. (btw
MajorKey returns enum which contains all "subclasses" so CodeStub already knows
everything about it's subclasses).

Nevertheless I agree that virtual functions are slightly cleaner way of doing
this. Done.

+    }
   }
 
   ASSERT(!NeedsImmovableCode() || heap->lo_space()->Contains(code));
   return Handle<Code>(code, isolate);
 }
 
 
 MaybeObject* CodeStub::TryGetCode() {
   Code* code;
   if (!FindCodeInCache(&code)) {
@@ skipping 18 matching lines @@
     }
     code = Code::cast(new_object);
     RecordCodeGeneration(code, &masm);
     FinishCode(code);
 
     // Try to update the code cache but do not fail if unable.
     MaybeObject* maybe_new_object =
         heap->code_stubs()->AtNumberPut(GetKey(), code);
     if (maybe_new_object->ToObject(&new_object)) {
       heap->public_set_code_stubs(NumberDictionary::cast(new_object));
+    } else if (MajorKey() == RecordWrite) {

[Lasse Reichstein, 2011/07/12 06:44:16]

Again, create a virtual function, e.g., MustBeCached(), that returns true on the
RecordWrite stub.

[Vyacheslav Egorov (Chromium), 2011/07/12 11:17:11]

Done.

+      // All RecordWrite stubs have to be registered in the stub cache.
+      return maybe_new_object;
+    }
+
+    // If this is a RecordWrite stub we need to patch it to ensure correct state.
+    if (MajorKey() == RecordWrite) {
+      heap->incremental_marking()->ActivateGeneratedStub(code);

[Lasse Reichstein, 2011/07/12 06:44:16]

And again.

[Vyacheslav Egorov (Chromium), 2011/07/12 11:17:11]

Done.

     }
   }
 
   return code;
 }
 
 
 const char* CodeStub::MajorName(CodeStub::Major major_key,
                                 bool allow_unknown_keys) {
   switch (major_key) {
@@ skipping 85 matching lines @@
   KeyedLoadStubCompiler::GenerateLoadExternalArray(masm, array_type_);
 }
 
 
 void KeyedStoreExternalArrayStub::Generate(MacroAssembler* masm) {
   KeyedStoreStubCompiler::GenerateStoreExternalArray(masm, array_type_);
 }
 
 
 } }  // namespace v8::internal